4 ms·

This reminds me of core rope memory [1], AKA "little old lady" memory, which was literally a ROM that was manually woven. [1] https://en.wikipedia.org/wiki/Cor

This reminds me of core rope memory [1], AKA "little old lady" memory, which was literally a ROM that was manually woven. [1] https://en.wikipedia.org/wiki/Core_rope_memory https://en.wikipedia.org/wiki/Core_rope_memory

eletious 8y ago
What were the actual ropes themselves made of? Just standard rope materials?
- c22 8y ago
  Copper. Edit: I found a neat video: https://youtu.be/X0WnddW5gZI https://youtu.be/X0WnddW5gZI
  - laumars 8y ago
    I’ve been programming for nearly 30 years and today I just learned that “bits” was derived from BInary digiTS. That’s an amazing video. Thank you for posting it.
    - MrEldritch 8y ago
      Also, "pixels" is from "PICture ELements"
      - kevin_thibedeau 8y ago
        "pels" was an early designation.
        userbinator 8y ago
        It's still used among video codec discussions, especially with the MPEG group.
      - raimonides 8y ago
        And byte is 'by eight'
_emacsomancer_ 8y ago
Which in turn reminds me of South American 'quipu': https://en.wikipedia.org/wiki/Quipu https://en.wikipedia.org/wiki/Quipu
GordonS 8y ago
> By the standards of the time, a relatively large amount of data could be stored in a small installed volume of core rope memory: 72 kilobytes per cubic foot, or roughly 2.5 megabytes per cubic meter Wow, I'd never heard of this 'rope' memory before - incredible!
kibwen 8y ago
On the topic of cool old memory technologies, see also mercury delay line memory, which involves a cylinder of mercury into which you transmit pressure waves to encode information, and to read it back you wait for the particular offset in time when the beginning of the data you need is reflected back to you: https://en.m.wikipedia.org/wiki/Delay_line_memory https://en.m.wikipedia.org/wiki/Delay_line_memory
- blattimwind 8y ago
  Sounds similar to surface acaustic wave filters and delay lines, which were e.g. commonly used in televisions (to make the color signal of the preceding line accessible while drawing the next line, it needs to be delayed by a line (64 µs). These work by turning the electrical signal into a mechanical strain wave travelling mostly on the surface of the substrate, where it can be filtered by mechanical means (think tuning forks, but etched into the surface) or simply delayed by the path length. The "receiving" end then turns the mechanical wave back into electricity.
amygdyl 8y ago
Likewise : The rope core memories would become know as "LOL memory" after the "little old ladies" who knitted together the software at a factory just outside Boston. These ladies would sit in pairs with a memory unit between them, threading metres and metres of slender copper wires through and around the cores. "But it is extremely robust - that information probably still exists despite being left on the Moon." http://news.bbc.co.uk/2/hi/technology/8148730.stm http://news.bbc.co.uk/2/hi/technology/8148730.stm

eletious 8y ago

What were the actual ropes themselves made of? Just standard rope materials?

c22 8y ago
Copper. Edit: I found a neat video: https://youtu.be/X0WnddW5gZI https://youtu.be/X0WnddW5gZI
- laumars 8y ago
  I’ve been programming for nearly 30 years and today I just learned that “bits” was derived from BInary digiTS. That’s an amazing video. Thank you for posting it.
  - MrEldritch 8y ago
    Also, "pixels" is from "PICture ELements"
    - kevin_thibedeau 8y ago
      "pels" was an early designation.
      - userbinator 8y ago
        It's still used among video codec discussions, especially with the MPEG group.
    - raimonides 8y ago
      And byte is 'by eight'

_emacsomancer_ 8y ago

Which in turn reminds me of South American 'quipu': https://en.wikipedia.org/wiki/Quipu https://en.wikipedia.org/wiki/Quipu

GordonS 8y ago

> By the standards of the time, a relatively large amount of data could be stored in a small installed volume of core rope memory: 72 kilobytes per cubic foot, or roughly 2.5 megabytes per cubic meter Wow, I'd never heard of this 'rope' memory before - incredible!

kibwen 8y ago

On the topic of cool old memory technologies, see also mercury delay line memory, which involves a cylinder of mercury into which you transmit pressure waves to encode information, and to read it back you wait for the particular offset in time when the beginning of the data you need is reflected back to you: https://en.m.wikipedia.org/wiki/Delay_line_memory https://en.m.wikipedia.org/wiki/Delay_line_memory

blattimwind 8y ago
Sounds similar to surface acaustic wave filters and delay lines, which were e.g. commonly used in televisions (to make the color signal of the preceding line accessible while drawing the next line, it needs to be delayed by a line (64 µs). These work by turning the electrical signal into a mechanical strain wave travelling mostly on the surface of the substrate, where it can be filtered by mechanical means (think tuning forks, but etched into the surface) or simply delayed by the path length. The "receiving" end then turns the mechanical wave back into electricity.

amygdyl 8y ago

Likewise : The rope core memories would become know as "LOL memory" after the "little old ladies" who knitted together the software at a factory just outside Boston. These ladies would sit in pairs with a memory unit between them, threading metres and metres of slender copper wires through and around the cores. "But it is extremely robust - that information probably still exists despite being left on the Moon." http://news.bbc.co.uk/2/hi/technology/8148730.stm http://news.bbc.co.uk/2/hi/technology/8148730.stm